Concentrating solar collectors operating at extreme concentrations (from about 500 suns to about 2,000 suns) require optimal cooling systems to dissipate heat that evolves in the photovoltaic cell from incident solar radiation. A variety of cooling methods are available including liquid cooling, forced air and convective cooling. Of these methods, convective cooling is often viewed as the most desirable for cost and reliability reasons.
A common strategy to implement high performance collection is to construct an array of concentrating solar collectors (Fresnel lenses for example). In such an array, each lens is associated with a given photovoltaic cell. In conventional designs, these photovoltaic cells must be individually packaged, structurally supported and cooled. These elements are structurally connected and move as a single unit to track the sun on a single two axis drive system. It is normal practice to electrically connect individual photovoltaic cells in series to enable system operation at higher voltage. In systems comprising many photovoltaic cells, this voltage is large and electrical isolation of components is necessary for safety and reliability.
Concentrating solar collector systems track the sun in order to maintain optical focus of the concentrated sunlight on the photovoltaic cells. In typical designs, the tracking must be accurate to angles of a degree or less relative to the sun. Tracking may be performed by rotating the assembly in the azimuth and then the elevation to follow the sun.
A cooling system affixed to a photovoltaic cell on a concentrating solar collector will therefore experience angular rotations ranging as much as from zero degrees to 90 degrees in elevation over the course of the solar day depending on the day of the year and geographic location. It is desirable that the cooling system operate optimally over this range of angles.
Therefore, techniques for cooling concentrating solar collector systems that perform optimally at different elevation angles and provide electrical isolation to the photovoltaic cells in the system would be desirable.